1. Field of the Invention
The present invention relates to a metal expansion joint and vibration absorber apparatus for pipe systems having at least one metal bellows element, at least one flange element adapted to be mounted to a respective adjacent structure, and having at least one protection sleeve element in form of a pipe stub located inside of and extending coaxially to the metal bellows element.
Metal expansion joints and vibration absorber apparatuses in pipe systems are predominantly used in two applications. A first application is the use of such apparatuses as expansion joint and a second application is the use as vibration absorber. In both applications the basically same design of the apparatus is used, whereby in case of expansion joints the primary operation of the apparatus is taking up displacements of pipes in a pipe system whereby such apparatus absorbs due to its design comprising a metal bellows element as secondary effect also possible vibrations in the pipe system. In case of vibration absorption the primary operation of the apparatus is absorbing vibrations in a pipe system whereby such apparatus takes up displacements of pipes in the pipe system as secondary effect. Also possible are applications in which the apparatus is used to take up displacements and simultaneously to absorb vibrations. The basic operating member of these apparatuses is its metal bellows which is calculated and designed regarding material, dimensions, etc. depending from the prevailing object, namely to absorb pipe displacements or then to absorb vibrations.
When such apparatus is used as pipe displacement absorbing apparatus it is called expansion joint.
Expansion joints are commonly used in pipe lines, pipe line systems and circuits in which for instance due to high or low temperature of the commodity flowing through the pipes the temperature of the pipes themselves increases or decreases accordingly leading to thermal expansions or contractions, resp. These expansions or contractions, resp. cause generally changes of the axial dimension of the pipes and also angular movements and lateral shifting displacements. In order to take such displacements up expansion joints are inserted between the pipe sections, whereby the metal bellows of these joints contract and expand such to take up mentioned changes of the dimensions.
The object of vibration absorbers is the absorption of vibrations in pipe systems in that the metal bellows absorbs vibrations or oscillations, resp. caused by the commodity flowing in the pipe system (turbulence), or vibrations stemming from a machine to which pipes are coupled, e.g. compressors or internal combustion machines, whereby in latter case the exhaust pipe or manifold is coupled via such a vibration absorber to the machine.
2. Description of the Prior Art
Metal expansion Joint and vibration absorbing apparatuses have commonly included a single or multiply bellows element made of a thin sheet of metal and formed with convolutions, which sheet metal bellows element is mounted e.g. by welding, soldering or clamping at both its end to respective flange elements via which the expansion joint or vibration absorber, resp. is coupled at both its ends e.g. via bolts or clamps to an adjacent pipe section of a pipe system or machine, resp. In order to protect the bellows from the commodity or fluid, resp. flowing through the apparatus and also to avoid turbulences in the fluid a protection sleeve can be arranged inside the bellows which extends coaxially thereto. This protection sleeve is generally mounted in one or the other way to one of the flanges. It may have an upturned end sandwiched between the flange of the expansion joint or vibration absorber, resp. and the flange of an adjoining structure, e.g. pipe, or it could be welded to the flange of the expansion joint.
Thus, the known expansion joints or vibration absorbers, resp. are assembled of a plurality of parts of various structural and physical properties. Accordingly, a manufacturer must keep a rather large amount of different articles for assembling such apparatuses in stock, the assembling of the apparatuses is time consuming because a plurality of individual articles must be assembled and finally, specifically due to the solid flanges, the known expansion joints and vibration absorbers, resp. have a relatively considerable weight.